The invention relates to an apparatus for displacing material lying on the ground transversely to the direction of travel, in particular a raking apparatus for mown crops, comprising at least two endless draw members operative in upright planes oriented transversely to the direction of travel, said draw members being arranged in tandem and mutually laterally offset relationship relatively to the direction of travel, and being interconnected by linkages, each consisting of an intermediate bar extending at least partly in an oblique direction relative to the direction of travel, at least one part of each linkage being designed as a carrier of downwardly directed rake tines.
Such an apparatus for raking hay is described in Dutch patent application No. 69.01862, laid open to public inspection on Aug. 10, 1970, and is designed in such a manner that the rake tines perform a substantially circular motion, said tines contacting the ground only shortly. Consequently, when the speed is increased for obtaining a larger capacity, the material will be strongly damaged due to the higher rake tine speed, resulting in the dreaded loss of leaf.
It is an object of the present invention to eliminate this drawback. To this end, a raking apparatus of the above described type is characterized in that the draw members are designed in such a manner that the rake tines perform a translation movement along the ground at least over a part of their path of movement. The rake efficiency can be further increased when each intermediate bar is provided on at least one end with an end bar oriented parallel to the direction of travel, right-angled to the working surfaces of the draw members and connected rotatably to the draw members, and both said end bar(s) and the intermediate bar is provided with downwardly directed rake tines. Moreover, a straight sweep-away or pick-up edge is obtained thereby.
For obtaining the above translation motion, the draw members may be fitted with tracks extending at least partly straightly.
The free end bars of each linkage oriented parallel to the direction of travel may be fitted with rollers adapted for coaction with a curve disc or track fitted with said straight track or a part thereof.
These ends may be interconnected two by two.
In a further embodiment of the present invention, when the raking apparatus comprises four linkages, the linkages may be interconnected two by two, and both resulting linkages may be interconnectec by means of a connecting rod whose centre is connected to a frame-mounted drivable swivel bar. In spite of a certain unbalance, a quiet course of the raking apparatus is thereby obtained during the execution of the contemplated motion pattern.
The latter is enchanced yet when the linkages are interconnected two by two by a bar rotatably connected to the swivel bar, said first mentioned bar being driven by an intermediate arm whose other end is rotatably connected to a lever affixed to the shaft. Such a construction ensures a still quieter course, without substantial accelerations and decelerations, than in case the swivel bar should be driven directly by the shaft.